I have said before and was serious, as long as the personal dimension of this discussion is in play, that if the US actually did get caught up in a hot war with Russia, I would join the military. There are, it may surprise you to know, some people younger than the "greatest generation" who would be willing to risk their lives for something worthwhile.
Like, you know global peace and integration. That's the crown jewel of our time and you bet your ass I'd risk bleeding out in a Ukrainian ditch to protect it.
Now that I've reiterated that let's bring it back away from the personal issues shall we? Yes it's garbage that the rich and old send the young and poor to die for their wars.
But some wars, ultimately, are just. I would fight in a just war. I would hate every second of it because the entire enterprise is one protracted tragedy, as any war is, but sometimes sadly, things do come to blows.
After WW1 the idea of a "war to end war" became a laughingstock. However, the point was made, and at this stage that is the only war that can be just.